Chest X ray interpretation

Question 1

What is the framework for reporting a chest x ray?

Answer 1

Patient’s name and DOB
Data of imaging
Technical considerations
Clinical review

Question 2

What are the technical aspects to be considered in a CXR?

Answer 2

Type of film
Position of patient
Projection
Orientation
Rotation
Exposure
Inspiration
Inclusion

Question 3

What is projection?

Answer 3

Refers to the direction at which the x-ray beam passes.

• Posterior-anterior
• Anterior-posterior
• Lateral (view from either the right or left side)

Question 4

What is one of the downfalls about using an AP film?

Answer 4

Due to divergence judgement should not be made on the appearance of the heart

Question 5

What is position?

Answer 5

Standard x-rays are taken with the patient standing

Any deviations from this will be marked on the film

Will allow you to make a better decision, i.e.

• sitting = unwell patient
• supine/prone - very unwell patient

Question 6

What is orientation?

Answer 6

Films should have position markers, i.e. R for right

The position should always be as if you are facing the patient

Beware: rare cases of dextrocardia

Question 7

What is rotation?

Answer 7

It should be ensured that films should be taken with the patient facing directly away from source

Look at spinous processes of the thoracic vertebrae (should appear centrally)

Look at distance between the medial ends of the clavicles and the spinous process of the nearest vertebra (should be equal)

Question 8

What is exposure?

Answer 8

The appropriate exposure depends on patient size.

• Too little => lungs appear too white
• Too much => structures appear too dark - lose subtlety

Should be able to make out vertebral bodies through the image of the heart

Question 9

What is inflation?

Answer 9

A CXR should be taken with fully inflated lungs

- there should be >= 9 ribs visible posteriorly

Question 10

What are the 5 basic densities on X ray?

Answer 10

Black = gas

Dark grey = fat

Light grey = soft tissue and fluid

White = bone and calcification

Intense white = metal

Question 11

Which structures should be looked at when making a clinical interpretation?

Answer 11

Heart and mediastinum

Hila

Bones

• vertebrae
• ribs
• lytic lesions

Soft tissue

Surgical emphysema

Breasts

Nipples

Abdomen

The lungs